Electric switch.



No. 543,730. Patented Feb. 20, i9'oo., w. T. PBINGLE. I

ELECTRIC SWITCH.

(Application filed July 19, 1899.)

(No Model.)

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UNITED STATES PATENT OFFICE.

l/VILLIAM T. PRINGLE, OF PRIMOS, PENNSYLVANIA, ASSIGNOR OF ONE-HALF TO EDWVIN R. KELLER, OF PHILADELPHIA, PENNSYLVANIA.

ELECTRIC SWITCH.

SPECIFICATION forming part of Letters Patent No. 643,730, dated February 20, 1900.

A licati fil d July 19, 1899- Serial No. 724,351. (No model.)

To all whom it may concern: 4

Be it known that 1, WILLIAM T. PRINGLE, a citizen of the United States, residing at Frimos, county of Delaware, State of Pennsylvania, have invented a new and useful Electric Switch, of which the following is a specification.

My invention relates to electric switches, especially to that class of switches termed flush switches, in which all the operative actuating parts are located behindaface-plate except the member to be manually operated.

One of the objects of my invention is to afford means for operating the movable contact member behind a face-plate by a manuallyoperative member projecting through a slot in the face-plate and having a direct and positive action upon the said movable contact member without the interposition of aspring between the two, so that the switch never ceases to be within the complete control of the operator by failure of the spring to act.

In the class of switches known as flush switches it has heretofore been a common practice to employ a spring intermediate the actuating member and the movable contact member, the function of the actuating menu her being to shift the points of spring connection past a dead-center, so that the spring shall then cause the quick movement of the movable contact member, the objection to this form of device being the uncertain or variable efficiency of the spring. In case it weaken or break the switch cannot be manually operated, and damage or inconvenience is the result. To overcome this objection is the chief object of my invention. I accomplish this object by the mechanism illustrated in the accompanying drawings, in which- Figure 1 is a side elevation of my device with the receptacle and face-plate in section, showing the switch open. Fig. 2 .is a similar view showing the switch closed. Fig. 3 is a front view of the face-plate, showing the manuallyoperative member extending therethrough. Fig. 4 is aview in detail of the manually-operative member.

Similar numerals refer to similar parts throughout the several views.

Referring to the drawings, the manuallyoperative member 5 is pivoted at 8, having its free end projecting through slot 14in faceplate 15. Said free end is provided with the handle 11. Upon member 5 is mounted and insulated therefrom a metallic plate provided 5 5 with a slot 6, adapted to cooperate with the projection 7 of the movable contact member 4, which is pivoted at 9 to move in a plane parallel with the plane of movement of themanually-operative member, the longitudinal 6o axes of said members crossing each other. The brushes or stationary contacts, with which the movable contact member is adapted to engage, are indicated by 2 and 3. In Fig. 1

the movable contact member is shown open or out of contact with the stationary contacts 2 and 3, in which position the projection 7 resides in the lower right-hand extremity of the slot 6 of the member 5. Upon the downward movement of the member 5, caused by pressure manually exerted upon the handle 11, the upper side of slot 6 engages with the projection 7 and forces member i into the closed position, as shown in Fig. 2. The

spring 10, which has a sliding connection with 7 5 loop 13,which is integral with member 5,serves to accelerate the movement of the actuating member 5 to cause the consequent acceleration of the member 4: just at the point of its breaking or making contact with fixed contacts 2 and 3 and prevent its remaining in imperfect contact or in a position dangerously near the fixed contacts by cause of insufficient movement of the member 5 to completely close or open the switch. Upon the actuating member projecting through the slot of the face-plate and having a movable but positive engagement with the contact member, and spring means adapted to be put under strain by the initial movement of the actuating member and then to be released to ac- I00 celerate the final movement of the switch, substantially as described.

2. In a finsh switch the combination of fixed connection, and spring means for cooperating terminals, a movable contact member adapted therewith for accelerating the final movement 10 to cooperate therewith, a slotted face-plate for of the actuating member in opening and closcovering said terminals and member, a maning the switch, substantially as described.

5 ually-operative member projecting through WVM. T. PRINGLE.

the slot of the face-plate and traversing the Witnesses: longitudinal extension of the contact mem- JNO. STOKES ADAMS, her and connected therewith by slot-and-pin MAE HOFFMANN. 

